A small circular loop of conducting wire has radius of 0.6 m is placed in a uniform field lines which make an angle of 25° with the plane of the coil. The coil is rotate at 2.5  N m with a of current 2.6 A. 

Calculate the magnitude of the uniform magnetic field that creates this torque.

Three long, parallel wires are separated in an isosceles triangle with d = 5 cm a

nd

carry currents 

Determine the resultant magnetic force per unit length on I₁ due to the wires I₂ and I₃.

A proton moves across a uniform magnetic field of 1.7 T with a radius of curvature for the motion 2.3 cm.  

Determine the speed of the proton in unit m s^-1.

Charge of proton = 1.6 × 10^-19 C and mass of a proton = 1.67 × 10^-27 kg. 

Two circular

coils of wire with radius 4 cm and 6 cm are placed on a flat surface. 

Both coils have 6 turns and carry current I = 4 A  in the same direction. 

Determine

the magnitude of the resultant magnetic field at the centre of the coils, P.